Syringe closure



May 4, 1954 c. B. BURNSIDE SYRINGE CLOSURE 7 Filed Nov. 7, 1952 INVENTOR. CARL B. BURNSIDE Patented May 4, 1954 UNITED S TAT PATENT OFFICE SYRIN GE CLO SURE Application November 7, 1952, Serial No. 319,227

Claims. 1

This invention relates to hypodermic syringes of the Luer-Lok or detachably-mounted needle type, and more particularly to a sealing closure therefor.

The present trend in the syringe art is to provide syringes that are expendable, such syringes icing generally known to the trade as of the disposable type. These syringes are generally made of an inexpensive plastic material such as polyethylene or the like and have their needles either threadably attached to or fixedly mounted on the syringe barrels. Means are provided for containing the medicament or injectable within the barrel such as by sealing the needle or sealing the barrel and using therewith a needle hav ing its opposite ends pointed, one pointed end piercing the barrel closure.

The Luer-Lok type of syringe, as is well known, has its needle secured to the syringe barrel by means of an interiorly tapered hub on the needle frictionally afiixed upon a correspondingly exteriorly tapered nozzle provided on the syringe barrel, projecting corners of the hub being adapted to threadably engage threads provided interiorly of a circular sleeve spacedly surrounding the tapered nozzle. This type of syringe is disclosed in U. S. Patents Nos. 1,793,068 and 2,676,121 granted to F. S. Dickinson on February 17, 1931, and April 6, 1937, respectively. In using this type of syringe, the barrel, plunger and needle, having been previously sterilized, are assembled together as shown in the above patents, the needle thrust through a seal of an ampoule containing the injectable, and the plunger withdrawn to draw the medicament or injectable upwardly into the barrel to an extent sufiicient to obtain the required dose amount. Thereupon, the needle is withdrawn from the ampoule or vial, and the injection administered.

With the growing trend toward the disposable type syringe it has :become desirable to render this .Juer-Lok or detachably-mounted needle type of syringe capable of being used as a disposable syringe, i. e., with the injectable con tained Within the barrel in readiness for mounting of the needle and forthwith proceeding with the injection.

Accordingly, it is an object of the present invention to provide a closur for a syringe of the Luer-Lok type which closure renders syringes of this character capable of containing the medicament ready for mounting the needle thereon and for use as a syringe of the expendable or disposable type.

A further object is to provide an inexpensive closure for a syringe of this character which simply but efiectively seals not only the nozzle of the syringe barrel but as Well serves to seal and maintain in an aseptic condition the area adjacent said nozzle which is contacted by the needle hub when the needle is assembled upon the syringe barrel.

These and other objects of this invention will become apparent to those skilled in the art upon becoming familiar with the following description when taken in conjunction with the accompanying drawings in which like parts are designated by like numerals and in which:

Fig. l is a perspective view of a Luer-Lok type of syringe with the needle affixed thereon,

Fig. 2 is a perspective of said syringe with the closure cap mounted thereon,

Fig. 3 is an enlarged, exploded perspective showing the needle-receiving end of the syringe barrel and. the interior of the closure,

Fig. 4 is a longitudinal sectional elevation of a portion of the syringe barrel with the closure mounted thereon, and

Fig. 5 is a sectional elevation of the closure member.

Referring to Fig. 1, a syringe of the Luer- Lok type is generally indicated at It. The syringe as herein shown is made of a semi-pliant plastic material such as, for example, polyethylene. It comprises a cylindrical barrel H molded or otherwise suitably formed with oppositely disposed finger-pieces H2 at one end thereof. The opposite end of barrel H has integrally formed thereon a nozzle l3 (Figs. 3 and l). The external surface M of nozzle l3 preferably is tapered longitudinally thereof as clearly shown in Fig. 4. A cylindrical skirt or sleeve i5 is similarly formed integrally with the nozzle-bearing end of barrel H, the sleeve 15 projecting in spaced relation from and surrounding the tapered, external surface of nozzle [3. The interior of sleeve 15 is provided with steeply pitched spiral threads is adapted to threadably engage the four corners of a square flange (not shown) provided on a hub I! (Fig. 1) of a hypodermic needle I S. The leading end i9 (Fig. 4) of nozzle l3 extends a short distance beyond the plane of the leading end 20 of sleeve l5.

The plunger of the embodiment herein shown comprises a flanged shank 2! (Figs. 1 and 2) having a thumb rest 22 provided thereon at one end and a plunger head 23 threadably or otherwise suitably secured at its opposite end. Plunger head 23 is formed of rubber or the like and is of such diameter as to frictionally engage the interior of a bore 24 in barrel H. Shank 2| may be moulded or otherwise formed of a plastic material such as polyethylene or polystyrene.

This type of syringe has heretofore generally been fabricated of glass. Therefore, in order to insure a suitable operative interfitting between the plunger and the barrel, expensive grinding or lapping operations were involved. By utilizing a semi-pliant plastic material for the barrel in combination with a rubber plunger head the necessity for employing the relatively expensive plunger-barrel fitting operations is eliminated and the cost of the syringe materially reduced. In this manner there is provided a syringe of the Luer-Lok type which is sufficiently inexpensive to manufacture to render it expendable, that is to say, to be discarded after a single use. As previously stated, in using this Luer-Lok type of syringe in its original form when its components were made of glass the customary procedure was to sterilize the components, assemble them in the form shown in Fig. l and then insert the needle through the seal (usually a rubber stopper) of an ampoule containing the medicament or injectable. Following this, the plunger was withdrawn into the barrel an extent cuff. cient to draw the injectable thereinto in the required dose amount.

With the components of the syringe manufactured of inexpensive plastic materials as he 'e tofore described it has become desirable to have this type of syringe capable of use as an immediate container for the medicament or injectable so as to render it suitable for use as an expendable or throw-away type of syringe.

To this end I have provided a closure cap generally indicated at 9. Cap 9 is formed of a semi-pliant plastic material such as poly-ethylone. The cap comprises a disk 25 (Fig. 5) provided with an annular recess 26 interiorly and centrally thereof. The inner wall of recess 25 is formed by an inwardly projecting, centrally disposed plug 21 preferably of such length as to extend a distance from a base 28 of recess equal to approximately one third of the length of nozzle it as shown in Fig. 4. The diameter of plug 2'? is preferably in excess of the diameter of bore 2Q of nzz1e E3 in an amount on the order of ten thousandths of an inch so as to provide a stoppering resistance fit between plug 2? and bore 25} when the closure is mounted on barrel as shown in Fig. i. The outer Wall St (Fig. 5) c1 recess 28 is preferably coriormabiy tapered to correspond with the taper of the leading end of shown in Fig. 4. The periphery of disk is formed with an inwardly projecting flange of such diameter as no fit snugly and sealingiy telescopically over the leading end of sleeve When closure 9 is mounted upon the syringe barrel as shown in Figs. 2 and 4, plug 2? enters substantial distance into bore 29 of the barrel effects a leak-proof, primary seal thereof. The base 23 of recess 26 and the outer wall 38 thereof, press-fittedly engage the corresponding surface portions l9 and i i of nozzle i3 and thereby snugly and sealingly seat upon these surfaces to effect a secondary seal. A tertiary seal is effected by the press-fitted engagement of flange 3i and the base wall 32 of disk 25 seating upon corresponding surface portions of sleeve 55. In this manner, a medicament or injectable contained within barrel Ii is positively sealed by the primary and secondary seals just described and, simultaneously, the area surrounding nozzle the external wall 14 of nozzle it as clearly I3, i. e., the interiorly threaded portion of sleeve I5 is aseptically sealed by flange 3| and base 32 as well as by the secondary seal provided for nozzle l3.

The substantial occupation of bore 29 by plug 2! insures that the bore will be kept free and open for the passage of the medicament therethrough when closure 9 is removed from sealing engagement with barrel ll. When the injectable contained in the barrel is of a thick, heavy or viscous type this provision whereby bore 29 is maintained free and open for the passage of the medicament is particularly desirable.

In production, the closure 9 and barrel II are rendered sterile in any suitable manner and the closure is seated upon the barrel as above de scribed and as shown in Fig. 4. Next, the medicament or injectable is aseptically introduced into the bore of the barrel and is aseptically sealed therein by the sterilized plunger head 23.

In preparing the syringe for injection it is merely necessary to remove a needle 18 from a sterile package and remove the closure 9 from its sealing engagement with barrel H. Next, grasping the needle externally of its hub 57 the latter is mounted upon nozzle l3 and the mounting secured by screwing the hub into threads ill of sleeve l5. Following the injection, if desired, needle may be retained and resterilizecl for subsequent use. The barrel H and plunger element 2| may be discarded.

Although the invention has been described with reference to certain particular embodiments it is to be understood that it is not limited thereby. Therefore, changes, omissions, Silk-Still tions and/or additions may be made without departing from the spirit of the invention as defined in the appended claims.

I claim:

1. In combination with a syringe of the class described, said syringe being formed of a semipliant plastic and including a barrel having a nozzle for detachably receiving a hypodermic needle and an interiorly threaded sleeve spacedly surrounding said nozzle and adapted to threadably engage a hub on the needle to positively secure the needle on said nozzle, a closure cap enclosing said syringe nozzle and said sleeve prior to the mounting of said needle, said closure cap formed of semi-pliant plastic, said closure comprising a disk having an annular recess formed internally thereof and adapted to snugly and sealingly seat on the free end of said nozzle, an inwardly projecting plug formed centrally of said recess and providing one wall thereof, said plug being of a diameter slightly in excess of the diameter of the bore of said nozzle and adapted to enter therewithin to positively seal the latter for containment of an injectable within the barrel, and an inwardly projecting flange formed on the periphery of said dish adapted to telescopically receive said sleeve whereby the space between the latter and said nozzle is aseptically sealed in readiness for aseptic mounting of the needle on said barrel.

In combination with a syringe of the class described, said syringe being formed of a semipliant plastic and including barrel having a tapered nozzle for detachably receiving a correspondingly tapered hub of a hypodermic needle, said barrel also having an interiorly threaded sleeve spacedly surrounding said nozzle and adapted to threadably engage said hub to posi tively secure the needle on said barrel, a closure cap detachably mounted on said syringe nozzle and said sleeve, said closure cap being formed of semi-pliant plastic, said closure comprising a disk having an annular recess formed internally thereof and adapted to snugly and sealingly seat on the free end of said tapered nozzle, an inwardly projecting plug formed centrally of said recess and providing one wall thereof, said plug being of a diameter slightly in excess of the diameter of the bore of said nozzle and adapted to enter therewithin to positively seal the latter for containment of an injectable within the barrel, and inwardly projecting flange formed on the periphery of said disk adapted to telescopically receive and surround said sleeve whereby the space between the latter and said nozzle is aseptically sealed in readiness for aseptic mounting of said needle on said barrel.

3. A combination according to claim 2 wherein said recess in said closure cap is tapered to correspond to the taper of said nozzle.

4. A closure member for a syringe of the detachably mounted needle type wherein a tapered bore in the hub of the hypodermic needle is adapted to be frietionally affixed to a correspondingly tapered nozzle provided on the syringe barrel and said hub is also externally threadably engaged interiorly of a threaded sleeve formed on the needle-receiving end of said barrel in spaced relation from said nozzle, said member comprising a cup-shaped cap of pliant plastic material adapted to snugly and sealingly surround and enclose said sleeve, an inwardly projecting plug provided centrally therein, said plug being of such diameter as to frictionally engage and leak-proofedly seal the bore of said nozzle, and an annular recess provided around and immediately adjacent said plug with the surface of the latter forming one wall of said recess, said recess being of a width and depth such as to snugly and sealingly receive the leading end of the wall of said nozzle when said plug is fully inserted into sealing engagement within said bore.

5. The combination with a syringe of the detachably-mounted needle type including a barrel having a tapered nozzle projecting therefrom and an interiorly threaded sleeve spacedly surrounding said nozzle, of a removable closure for containing an injectable within said barrel and aseptically sealing the needle mounting area thereof, said closure comprising a disk-like cap having centrally thereof a portion recessed conformably to and snugly seated upon the projecting end of said tapered nozzle, an inwardly projecting plug providing an internal wall of said recess and entering frictionally within and sealing the bore of said nozzle, and an inwardly projecting flange provided peripherally of said disk telescopically surrounding and sealedly engaging the leading end and a portion of the external wall of said sleeve whereby an injectable is aseptically contained within said barrel and the space between said sleeve and said nozzle is maintained in an aseptically sealed condition ready for mounting said needle upon said barrel following removal of said closure.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,115,561 Northey Nov. 3, 1914 2,193,489 Nevin Mar. 12, 1940 

